Woodland Watch – Week 15 – 26/06/2013

Summer seems to finally be here and although it is neither as warm or as predictable as we would like, at least it is not as cold as it has been! This week my walk in the woods was overcast, but warm and I hope you will join me to have a look at what is going on this week.

The grass in the meadow approaching the wood is getting taller and taller but closer to ground level you can see lots of little purple clover flowers.

Clover growing in the hay meadow

Clover growing in the hay meadow

This red clover (Trifolium pratense) is a native, herbaceous perennial plant which can grow 20-80cm tall. The genus is so named because of the leaf structure consisting of three leaflets, known as trifoliate leaves. Clover is an interesting plant, widely grown as a fodder crop and highly valued for its nitrogen fixing capabilities which increase soil fertility.

Nitrogen fixation is the process by which nitrogen in the atmosphere is converted into ammonia. In the atmosphere nitrogen exists as a diatomic molecule (the atoms go around in pairs, like oxygen). In this inert state it does not easily react with other chemicals to form new compounds. Nitrogen fixing nodules in the clover plant frees up the nitrogen atoms from their chemical diatomic form (N2) to be used in other ways.

Before the establishment of science, when peopled looked to religion and magic for medicinal cures, red clover was already playing a part in people’s lives. To early Christians, it was a sign of the Trinity while during the Middle Ages, it was regarded as a charm against evil. A mutation resulting in the well-known four-leaf clover is considered good luck when found, even to this day.

Heading into the woodland, the first difference that was immediately apparent was how dark the wood was compared to previous weeks. The canopy has now almost completely closed over with a hazel lower canopy and an upper canopy made up of a range of other broad leaf trees including oak and horse chestnut.

The woodland was noticeably darker now the canopy has closed over

The woodland was noticeably darker now the canopy has closed over

One of the lower level tree species that we haven’t yet touched on but which I have noticed on my walks is the holly (Ilex aquifolium). An evergreen shrub which most people can easily recognise it can grow 10-25m tall with sharp spiney leaves which last around 5 years. What many people don’t realise, and to the relief of tree surgeons such as ourselves, is that leaves on the upper branches of mature trees do not have spines as they are well out of the reach of grazing animals and do not require this particular defense mechanism. 

Lower leaves of a mature holly tree

Lower leaves of a mature holly tree

Holly is dioescious which means there are male and female plants, unlike the hazel which we saw developing the male catkins and female flowers on the same trees. The sex of the plants cannot be determined until they begin flowering, usually between 4 and 12 years of age. Between October and November, the flowers on the female plants will grow into red fruit which is eaten by birds and rodents.

Interestingly in the Irish/Gaelic ogham alphabet holly is called Tinne, a word believed to have originally meant ‘fire’. From this was derived the word ‘tinder’, referring to dry, inflammable matter used for kindling fire from a spark. This association between holly and fire has been known since ancient times when charcoal made from holly wood was used by armourers to forge swords and axe heads.

The holly will remain fairly constant through the changing of the seasons, but it is a highly valuable woodland species.

Sticking with the theme of trees, another species to note is the English elm. Once a classic English tree like the English Oak, the elm all but disappeared from our countryside after Dutch Elm Disease reached Britain in 1927.

Now, these small elm saplings around the edge of the wood, although relatively common at this stage of their lives, are unlikely to reach maturity.

English Elm saplings

English Elm saplings

The current DED epidemic is caused by the fungus Ophiostoma novo-ulmi which is dispersed by various elm bark beetles within the Scolytus genus. The fungus blocks water conduction, resulting in wilting and eventual death of the foliage.

The first signs of the disease are often yellowing/browning of foliage tips as the affected branches are gradually starved of water.  When the leaves fall, the remaining twigs often turn down to form ‘shepherds crooks’ which can be valuable for disease detection in winter.

The diagram below shows how the disease progresses.

Dutch Elm Disease

Dutch Elm Disease

Although the English landscape has certainly lost the majority of its mature English elms, the Ulmus procera species has not disappeared completely from the landscape. This is because the elm bark beetles require bark to be of a certain thickness for breeding to be successful.

When an English Elm is killed by the disease, some roots remain alive and new elms regenerate from these. This means that for every mature elm killed by DED, many more are able to replace it. We may not have many large elms, but there are millions of young elms growing all over the English countryside, such as these young saplings in our wood.

That’s it for this week. Join us again next week for another walk in the woods.

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Woodland Watch – Week 13 – 12/06/2013

Welcome to another week and another walk in the woods. I have been amazed watching this woodland week by week, seeing all the changes and this week was just as exciting. So, here we go!

One of the standard trees in this woodland that we haven’t really looked at yet is the oak. There are several oak trees around the site, both young and mature specimens. This year, with the cold start to spring it took the oak trees a while to come into leaf. As you can see now, the oaks are properly in leaf and their vibrant green leaves provide a beautiful upper canopy to a few areas of the wood.

Looking up through the oak canopy

Looking up through the oak canopy

Of all our native trees, the oak is probably one of the most commonly recognised by people. Widespread in fields, hedgerows and woodlands it is arguably one of the classic English trees. There are over 400 species of oak worldwide including trees, shrubs, deciduous and evergreen varieties and they can live up to 700 years old, outliving all other trees in the UK except the yew.

In this woodland we have the native English Oak. Male catkins appear on the tree with the leaves in April and become long, pollen-filled pendulous by May. Then the female catkins open as upright flowers which await the touch of fertilising pollen from the males. They hold the seed vessels which will become acorns, the fruit of the oak tree.

I will look out for these in the coming weeks. For now, here’s another beautiful picture of the leaves of a young oak tree, bright and vibrant with new life.

Bright young oak leaves

Bright young oak leaves

We already noted last week the dramatic change in the colour of the woodland floor. Only a couple of weeks ago it was covered in the vivid blue of the bluebell flowers. Last week we saw the change to green as the flowers disappeared and the leaves started to wilt.

Bluebells reproduce through propagation by seed using sexual reproduction. They are usually pollinated by insects and after fertilisation occurs, the seeds are produced and dispersed. In the woodland, now that the flowers have disappeared you can clearly see all of the seed pods still standing on the upright stalks. Right now the seeds are still green, but they will turn darker as they mature before they are ready to disperse.

Bluebell seed pods

Bluebell seed pods

Going back a few weeks, before the hazel leaves burst into life we looked at the male catkins and female flowers and how the hazel reproduces. Now that this has happenned and the female flowers have been fertilised, the male catkin has fulfilled its purposes and drops off, leaving the female to produce the nuts that we will see in autumn. Walking around the wood, you can see many of the used, male catkins on the woodland floor.

Male catkins drop off once they have fertilised the female flowers, leaving them to develop into nuts ready for autumn.

Male catkins drop off once they have fertilised the female flowers, leaving them to develop into nuts ready for autumn.

And sticking with the theme of reproduction, the hawthorn has also just come into flower. Later than in most years but making a beautiful sight, especially around the boundaries of the wood where this photo was taken.

Hawthorn flowers coming into bloom on the edge of the wood

Hawthorn flowers coming into bloom on the edge of the wood

These blossoms contain both male and female reproductive parts and are fertilised by passing insects. By summer the seeds will grow into small green berries which will turn dark red by autumn to attract birds who will eat the berries and propagate the seeds. We will watch the hawthorns in the woodland as they move through this cycle.

And that’s it for another weekend of woodland watch. Join us next week for another walk in the woods!

In the meantime don’t forget to check out our website http://www.tree-creeper.com and send us any of your own woodland watch pictures from your own walks to office@tree-creeper.com or send them through our facebook page!

Woodland Watch – Week 9 – 15/05/2013

Welcome to another week in the woods. I’m sure I don’t need to tell anyone that the weather so far this spring is very unpredictable! So far I have been very lucky with my weekly woodland walks and have managed to do all of them in dry weather, but I think that probably has more to do with careful timing than anything else!

The woodland is made up mainly of hazel coppice with a range of standards dotted throughout but mainly around the edges of the woodland area. It was lovely to see the oaks starting to come into leaf. In folklaw the saying goes “If the oak before the ash, then we’ll only have a splash, if the ash before the oak, then we’ll surely have a soak.” This year however, the ash and oak have both held on for a long time before bursting into leaf and when they have they have appeared around the same time. I will leave you to draw your own conclusions as to what this could herald for the coming summer!

Oak standards on the woodland edge

Oak standards on the woodland edge

After a slow start the oak standards around the woodland are now starting to come into leaf. The oak tree has a wide range of qualities suitable for healing purposes. If ground into fine powder, oak bark can be taken like snuff to stop nosebleeds. It can also be sprinkled onto sheets to alleviate the discomfort of bedsores. Young oak leaf-buds were prepared in distilled water and taken inwardly to assuage inflammations and bruised oak leaves are used outwardly, being applied to wounds and hemorrhoids to ease inflammations.

Another plant with a great range of uses including medicinal is the common nettle (Urtica dioica). Seen emerging and starting to take hold in previous weeks, the banks of the stream bordering the woodland are now overrun with thick, impenetrable stinging nettles which are now out-competing most other flora in the area.

Stinging nettles overrunning the borders of the woodland

Stinging nettles overrunning the borders of the woodland

Around the woodland floor, the male ferns which were seen emerging with curled fronds in previous weeks are now fully unfurled and growing quickly.

Young ferns now unfurled and growing rapidly

Young ferns now unfurled and growing rapidly

Among the many weed species taking hold all over the woodland floor are the dandelions. Much less prevalent than in the surrounding open meadows and field, but nonetheless still present.

Young dandelion leaves nestled among the other ground flora

Young dandelion leaves nestled among the other ground flora

The word Dandelion comes from the French name for the plant dents de lion meaning teeth of the lion and refers to the jagged edges of the leaf of the plant. The other French name for this plant is pis-en-lit, in English this means wet the bed. Dandelions deserve this name because their greens, when eaten, remove water from the body. So eating the greens could cause someone to well… you can guess the rest. Not recommend for a bedtime snack.

The Dandelion provides an important food source to bees. The pollen from this plant helps bees out in the spring because it flowers early and the flowers continue through to the fall providing constant food. In fact no less then 93 different kinds of insects use Dandelion pollen as food. The Dandelion seeds are also important food to many small birds.

Join us next week for a wander through the woods with Woodland Watch Week 10

Woodland Watch – Week 5 – 17/04/2013

It’s all starting to happen in the woods now. With the warmer weather drifting in, albeit in fits and starts, everything seems to finally be trusting that it is safe to come out of hibernation. This week, everything seemed to be bursting into life, wherever I looked there were signs of spring and listening to the birds singing in the trees and hedgerows passed a beautiful half hour wandering around the woods.

One of the first new plants I noticed on entering the woods was self heal (Prunella vulgaris) starting to flower around the edges of the woodland in the grassy ecotone. Self-heals are low-growing plants, and thrive in moist wasteland and grass, spreading rapidly to cover the ground. They are members of the mint family and have the square stem common to mints. They flower from late spring through to autumn and add another touch of colour to the ground as you enter the woodland.

Self heal growing on the grassy boundaries of the woodland edge

Self heal growing on the grassy boundaries of the woodland edge

Up until today the majority of the trees and lower level canopy remained stubbornly in bud with only the young elder leaves brave enough to emerge. It was good to see the hazel buds bursting into life, showering the woodland at eye level with bright green emerging leaves.

Most of this woodland is comprised of coppiced hazel (Corylus avellana) and in the past hazel has been crucially important as a source of wood which grows into straight poles when cut at ground level (coppiced). Uses include thatching spars, net stakes, water divining sticks, hurdles, furniture,  firewood and many many more. Hazel nuts were prized as a food source in the past, however grey squirrels often strip the trees before the nuts can ripen and be harvested.

Bud burst on coppiced hazel

Bud burst on coppiced hazel

Also starting to come into leaf is the common English wild honeysuckle (Lonicera periclymentum). I was glad to see honeysuckle in the woodland as it is an important plant for dormouse habitat. Dormice shred honeysuckle bark and weave it into a ball to form their nests and although I have yet to spot signs of dormice in this coppice woodland, it is good that it has potential as dormouse habitat.

English wild honeysuckle

English wild honeysuckle

The elder (Sambucus nigra) is certainly the most advanced tree/shrub in the woodland in terms of leaf development now. Also part of the honeysuckle family, elder provides a wealth of flowers and fruit throughout the year feeding a wide range of birds, animals and insects.

Elder leaves are one of the most developed in the woodland so far

Elder leaves are some of the most developed in the woodland so far

And its not just the hazel and elder bursting into leaf, there are a lot of young hawthorn plants making up the shrub layer of the woodland and their bright young leaves are also starting to emerge.

Young hawthorn leaves emerging

Young hawthorn leaves emerging

That’s it for this week. Join us again for a walk in the woods and see what you see on your own walks. Let us know at http://www.tree-creeper.com or send us your photos on our Treecreeper Arborists facebook page.